Cloudera Hadoop Developer Certification Questions and Answer (Dumps and Practice Questions)

Question : Mapper and Reducer runs on the same machine then output of the Mapper will not be transferred via network to the reducer

1. True
2. False


Correct Answer : 1


Explanation: If Mappers and Reducer runs on the same node, then there is ni need of transferring the data over the network.
Which will reduce lot of network overhead.

Refer HadoopExam.com Recorded Training Module : 3 and 4





Question : No reducers can start until all the mappers have finished ?

1. True
2. False



Correct Answer : 1


Explanation: The reduce() method in the Reducers cannot start until all the Mappers have finished.

In practice, Hadoop will start trnsfer data from Mappers to Reducers as the Mappers finish work.

The developer can specify the percentage of Mappers which should finish before Reducers start

retrieving data.

The developers reduce method still does not start untill all intermediate data has been transferred and sorted.

Refer HadoopExam.com Recorded Training Module : 3 and 4





Question :

Hadoop will start transferring the data as soon as Mapper finishes it task and it will not wait till last Map Task finished

1. True
2. False

Correct Answer : 1


Explanation: In practice, Hadoop will start trnsfer data from Mappers to Reducers as the Mappers finish work.

The developer can specify the percentage of Mappers which should finish before Reducers start

retrieving data.

The developers reduce method still does not start untill all intermediate data has been transferred and sorted.

Refer HadoopExam.com Recorded Training Module : 3 and 4

Related Questions

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Question : A combiner reduce the amount of data sent to the Reducer ?


1. True
2. False


Question :

Combiner reduces the network traffic but increases the amount of work needed to be done by the reducer ?


1. True
2. False


Question :

Which is the correct for Pseudo-Distributed mode of the Hadoop


1. This a single machine cluster
2. All daemons run on the same machine
3. It does not require to run all the daemon in this mode
4. All 1,2 and 3 are correct
5. Only 1 and 2 are correct





Question :

Which daemon is responsible for the Housekeeping of the NameNode ?

1. JobTracker
2. Tasktracker
3. NameNode
4. Secondary NameNode




Question :

Which daemon is responsible for insantiating and monitoring individaul Map and Reduce Task

1. JobTracker
2. TaskTracker
3. Seconary NameNode
4. DataNode



Question :

Which Daemon distributes individual task to machines

1. TaskTracker
2. JobTracker
3. MasterTracker
4. NameNode
Solution : 15